1. Field of the Invention
The present invention relates to an operating field securing device which comes into contact with an internal organ such as the heart to perform various procedures and the like during surgery on the internal organ.
2. Description of the Related Art
In conventional cardiac surgery, the chest cavity is accessed by incising a breast bone (median breast bone incision). Moreover, when the chest cavity is accessed as described above, a retractor is disposed at a position of the breast to be incised, and the breast bone and tissue are spread by the retractor, thereby forming a large opening. Then, a surgical instrument is disposed through the opening to perform the cardiac surgery.
Meanwhile, one of the most general types of cardiac surgery is coronary artery bypass grafting (CABG). In CABG, when one or a plurality of coronary arteries are blocked, the coronary artery on the downstream side of this blockage is connected to a transplanted blood vessel (hereinafter referred to as the graft) to provide a bypass.
A technology for connecting the graft to the coronary artery in this manner is known as anastomasis. As the above graft, for example, a thoracic artery incised from a chest wall is used. In this case, the upstream end of the thoracic artery is left undamaged, and the downstream end of the thoracic artery is connected to the coronary artery.
Moreover, as the graft; an artery or a vein from any part of a patient's body may be used. Furthermore, an artificial blood vessel graft may be used as the graft. In this case, the upstream end of the graft is connected to an artery such as an aorta, and the downstream end thereof is connected to the coronary artery. As described above, a plurality of blocked coronary arteries at various positions of the front, side and back of the heart are bypassed by using a plurality of grafts.
It is to be noted that CABG is performed while the patient's heart is stopped. Therefore, the patient's blood is circulated by using an artificial heart-lung device. However, CABG may be performed by using a technology known as “off-pump coronary artery bypass” (OPCAB) while the heart is beating. That is, the use of the artificial heart-lung device can be avoided owing to OPCAB.
In OPCAB, while the heart is beating, the surface of the heart near the region of the coronary artery to be anastomosed is fixed by using a special instrument referred to as a stabilizer. Since the surface of the heart is locally fixed by this stabilizer, the region to be anastomosed is kept to be as immobile as possible while the graft is connected to the coronary artery.
Here, the stabilizer includes, for example, a contact portion which comes in contact with the surface of an internal organ, and a flexible contact portion support portion for supporting the contact portion. The contact portion support portion is constituted of a plurality of joining members so that the contact portion support portion can be bent or deformed.
Moreover, an elongated cable such as a wire is extended through the joining members. The tension of this cable is appropriately regulated to bend or deform the contact portion support portion, thereby inserting the contact portion support portion into the chest cavity. Then, the contact portion is brought into contact with a target region of the surface of the heart in the chest cavity, and the surface of the heart is pressed or adsorbed by the contact portion to suppress the vibration of the heart. Since the vibration of the heart is suppressed in this manner, an operating field securing device including a manipulator for performing various surgical procedures can be used to accurately operate on the heart. It is to be noted that the above technology concerning the stabilizer is disposed in, for example, Japanese Patent Publication No. 2003-521296.